Update configs and build scripts

build.sh

@@ -1,16 +1,35 @@
 #!/bin/sh
 
+image="antora/antora"
+cmd="--html-url-extension-style=indexify site.yml"
+
 if [ "$(uname)" == "Darwin" ]; then
     # Running on macOS.
     # Let's assume that the user has the Docker CE installed
     # which doesn't require a root password.
-    docker run --rm -it -v $(pwd):/antora antora/antora --html-url-extension-style=indexify site.yml
+    docker run --rm -it -v $(pwd):/antora $image $cmd
 
 elif [ "$(expr substr $(uname -s) 1 5)" == "Linux" ]; then
     # Running on Linux.
-    # Let's assume that it's running the Docker deamon
+    # Check whether podman is available, else faill back to docker
     # which requires root.
-    echo ""
-    echo "This build script is using Docker to run the build in an isolated environment. You might be asked for a root password in order to start it."
-sudo docker run --rm -it -v $(pwd):/antora:z antora/antora --html-url-extension-style=indexify site.yml
+    if [ -f /usr/bin/podman ]; then
+        runtime="podman"
+    else
+        runtime="docker"
+    fi
+    if groups | grep -wq "docker"; then
+        # Check if the current user is in the "docker" group. If true, no sudo is needed.
+        echo ""
+        echo "This build script is using $runtime to run the build in an isolated environment."
+        echo ""
+        $runtime run --rm -it -v $(pwd):/antora:z $image $cmd
+    else
+        # User isn't in the docker group; run the command with sudo.
+        echo ""
+        echo "This build script is using $runtime to run the build in an isolated environment. You might be asked for your password."
+        echo "You can avoid this by adding your user to the 'docker' group, but be aware of the security implications. See https://docs.docker.com/install/linux/linux-postinstall/."
+        echo ""
+        sudo $runtime run --rm -it -v $(pwd):/antora:z $image $cmd
+    fi
 fi